IRS Form 8938, the "Statement of Specified Foreign Financial Assets," is used by U.S. taxpayers to report certain foreign assets under FATCA. For those living or traveling abroad, singles or separate filers report assets over $200,000 at year-end or $300,000 anytime, while joint filers report over $400,000 at year-end or $600,000 anytime. Penalties include a $10,000 initial fine, up to $50,000 for continued failure, a 40% underpayment penalty, and potential criminal charges.